Saturday 27 April 2013

Update on last race day

I started pulling my car apart yesterday to get it ready for the next outing and discovered that I had bent ANOTHER upper control arm turnbuckle! Same side as the first. I have no idea what actually caused it, but I am wondering if its not the end of one of the anchor ropes used as track barriers. Its the only thing I can think of that I remember hitting twice during the weekend.

After not bending one in a year of racing previous to this, its quite amazing to me to bend 2 in the space of 4 races.



Monday 22 April 2013

Tough Day at the Office - Race Report 21/04/2013

Well after a week of prep and even longer anticipation, the actual day turned into a bit of a struggle really. I got the track conditions completely wrong and therefore none of the tyre combinations I had worked well enough for me to have any real impact on the results. Early signs looked promising, managing some mid 24 second laps in my shortened practice time, but then it was pretty much all down hill. As the track temperature rose the conditions moved outside the tyres performance range.

Practice
I arrived a bit later than I intended, mostly because I left later than I'd planned. There was not much I could do about the 2 hour drive, so I just had to setup as quickly as possible and try to get a bit of track time. I was trying a new Shimizu tyre combination based on info from http://rcformula1.com.au/index.php/tech-tips/tyres as well as the little bit of data I gathered from a quick visit to the same track a couple of months ago. The weather was supposed to be mild with temps in the low 20's, and in reality it probably never went over the predicted 24 degrees, but the exposure of the track and perfectly clears skies meant the track was bathed in quite hot sunlight and sucked in heat much faster than I was anticipating. Talk around the track was that it would get slower as the day went on.

My first practice run was encouraging with a couple of laps needed to scrub in the new tyres and then lay down a few fast laps. Car handling was good with just a little bit of entry push and then a little exit over-steer if I got on the power a little too hastily. I like to use steering dual rate to tune steering characteristics during a race, and the push was making me use more steering throw than I preferred. I wanted to test another tyre combo so I only did half a dozen laps and tried a softer front tyre. This gave me a whole heap more steering but its was almost too much and certainly on one particular corner, where the corner entry was preceded by some bumps, it was very unsettled compared to the previous combo. With racing starting in only 10 minutes I went back to the pits and changed back to the original tyres with a change to a softer spring on the front to try and add steering.

Race 1 - Result : 12/ 6m24.318s, Fastest lap - 24.613s
The drivers briefing revealed the first surprise of the day for me - 15 minute final. This hadn't been mentioned anywhere previous to this, or on the entry form. I wasn't upset, but only having 3, 6 minute qualifiers to sort everything out, considering it was also the first time I had run a 21.5 motor, was going to prove a challenge and so it turned out to be.

Most events I've attended in the recent past allow the drivers to do a couple of warm up laps before gridding up, to ensure everything is working and allow the race director to check transponders are registering. This is where I made my first mistake, clipping a corner marker. Initially there appeared to be no damage but I checked my trims and made a slight adjustment, then I gridded up. I started 1st thanks to random grid orders for the first race and I made a reasonable start. The first couple of minutes seemed to show everything going well. There were some fast guys in the field (including a former TITC class winner) so I was more than chuffed to hear my name being called out in 3rd position. It was at about the 3 minute mark that the car handling started to go away quite badly - the front became quite "darty" and the rear progressively moved to snap over-steer on corner exit, and that was despite using a function on my radio that helps me smooth my, sometimes itchy, throttle finger.

Back at the pit table, the front end damage that hadn't been obvious from the stand was now startling clear with a bent upper control arm turnbuckle. In all the time I've used the 3Racing front end, I've never bent one before. The end result was about 45 degrees of castor on one side compared to the other. It was probably surprising the car was as fast as it was. A quick repair was effected and also a change in gearing, going up 1 tooth on the pinion as it was obvious the difference in straight line speed on the long main straight.

Race 2 - Result : 3/ 2m14.506s , Fastest lap - 25.224s
I ran a longer warm up to gauge where I was with tyres and it was quickly obvious the combo I had chosen was not going to work for a 6 minute race, let alone a 15 minute race. I rushed back to the pits and changed the rear tyres for something I had more experience with but this was even less effective. I'd forgotten to pack my temperature gauge so I could only guess at the track temps but another racer I've known for years informed me they were getting into the 40+ degree area despite the cooler air temperature. This is probably also reflected in the lap times as, though more cars were dipping into the 23 second range, the fastest overall lap was only 0.1 of a second faster than the first race. 

I ran out of time to try anything else during the race but I manged to snag some practice time in the 10 minute break between rounds. I resorted to the the Ride A/B combination I had used in WA in the warmer weather and this appeared to be a step in the right direction. The car was much more stable but with a lot of push, but at least it stayed consistent, without a major change in handling as the tyre temps rose

Race 3 - Result : 13/ 6m24.453s, Fastest lap - 25.915s
This was all about trying to get a drivable car for the 15 minute final. I'd treated the front tyres with traction compound (something I HATE fiddling around with). It was obvious the track was slowing as even the faster guys were now struggling to stay in the 23 second range. I was managing high 25's and low 26's but it was a struggle to stay consistent, lacking patience with the under-steering car, something the F1-09 has never been. I was also now personally struggling quite badly with pain in my back, which had been giving me issues since a fall a week before.

Another ponder at the pit table and I decided the only change I would make was to the front steering knuckles, swapping to 0mm ones instead of the -3.5mm. In theory this should've given greater steering response and made the car turn into the corners harder. Also geared up one more tooth.

Final - Result : 32/ 15m19.442s, Fastest lap - 26.167s
By now the clouds had moved in and the sun had been blunted a bit. The track was still hot though and again this reflected in the lap times, with only one driver managing to match his earlier time. For me it was a case of circulating around and making the finish, which I was determined to do. The change to the car and even full treatment of the front tyres with traction compound really didn't achieve anything and the car was the slowest it had been all day, despite being much closer to the pace down the straights and not seeming to lack anything under acceleration. I just couldn't carry any corner speed if I wanted to make apexes and its backed up in the lap times and result - 5 laps behind the winner.

Overall
I have to admit I am disappointed with the result. I was never expecting to win, but to end up the slowest car in the field was never something I suspected might happen. I can pose some excuses like, having only my 1st "proper" race in 5 months, not having a lot of experience at that particular track, and first time running 21.5 but some of the other racers could also say any one or combination of those things.

As far as my driving was concerned the big disappointment was my consistency.  Being able to turn consistent lap times is something I've prided myself on in the past, but on this occasion it was severely lacking, being in the 1-2 second range. This can partly be attributed to car setup and track experience but mostly to crappy driving.

Setup wise I feel tyres was the big issue here. I simply didn't have a combination that was a close enough match for the track conditions, and any changes I made to the car to compensate were like a flea jumping on an elephant. Most of the fast cars were 180mm/190mm running the Ride R1 tyres and clearly, these ARE the tyres of choice at the moment, but using a 200mm car prevents me using those. I didn't get a chance to run my more traditional TRG/Shizimu combination. 

I also don't feel the Tekin RS ESC suits what I am trying to do with the car. For me, it lacks both throttle smoothness and strong brakes when used in combination with my car and radio, and nothing appears to affect that. With an under-steering car I should've been able to use the brakes to help turn the car but the Tekin brakes simply weren't strong enough. 

Whats next? Well I was informed of an online shop selling quality, name brand and ROAR approve short lipos for quite small amounts of money. Considering several of the cars in the field were using them I don't fear being sold a dud product. With these I can focus more on my 190mm car, which is probably a better way to focus rather than continuing to persevere with the 200mm car. The next round of the Interclub is not until June, but there should be a couple of club days and maybe another trip to Logan for a club day as well.

Of course if I buy a new chassis, whatever it may be, then it will be that I will focus on.

Friday 19 April 2013

The things we do - F1-09 Pod Modification


I've spent most of my spare time this week getting my F1 ready for the Logan interclub round. This has mostly involved replacing a few worn suspension pieces, glueing tyres, and fitting a new Speed Passion 21.5. This is where the real fun started.

Now I have nothing against SP products. I've used one of their ESC's on and off for years and have been using their motors in my occasional forays into mod tourer. However, they tend to have a touch of individuality about them and this is most obvious in their wiring on their motors. Unlike most brands that group the 3 connection at one point of the motor, SP decided to place them individually at 3 points around the circumference. 


Unfortunately this prevents the motor from fitting into the original F1-09 motor pod. With little time and no extra cash available to source a different brand of motor some modifications were required.


Original pod plate - this is the non-motor side

Modified pod plate - not quite a rough as it looks in the picture
Fortunately the F1-09 has a full top plate as part of the pod so there shouldn't be, and so far there doesn't appear to be, any extra flex. It does allow much more room for motor wiring, which inversely allowed me to run shorter wires. Rather than having to run the wires out through the top of the pod I can now run them out along the side. This doesn't interfere with the action of the rear suspension either.

Only a couple of days left to see how it goes. There isn't a huge field (9 cars at last count) but the names entered represent some high quality drivers.

Thursday 11 April 2013

Its OK.. I'm not dead

I haven't had much to write on this lately. Money has been really tight after the move from WA so racing toy cars hasn't really been something I can justify. I've been keeping an eye on all the different forums and sites and seen the release of a couple of new cars. The one that has caught my eye the most (after months of wanting a 3Racing F113) is the new SpeedPassion SP-1. It just seems to me to have a good thought process behind it, and I really like the front suspension layout, which allows all the different widths without buying option or extra parts. Possibly the only area I personally don't "like" is the friction roll shock, but that's nit picking. The price is also pretty good. Its 99% possible this will be my next F1.

I keep reading rumors about a narrowing kit for the F113 and if it appears in reality it might make the decision a bit harder, but until it appears the SP is my new first choice

I will be going racing F1 shortly. I'm planning to do the Interclub at Logan in Brisbane (which held the 2012 On Road Nationals) as F1 will be run. I don't really care about the whole interclub thing as technically it doesn't apply to me but racing will be fun. I'll be using My F1-09 in 200mm setup because I can't get batteries to suit the 190mm version. The 190mm car needs short lipos to be setup properly but the 200mm doesn't seem as touchy and I can use my full size battery packs. I am not expecting to win but I am hoping to have some fun.

I have done a little bit of racing in 4WD tourer however. I managed, finally, to get to my new local club, and even though the turnout was a bit small, I did a few runs in my rebuilt Tigermoth LCG. Despite having year old tyres,  a 3 year old 17.5 and an even older SP ESC I was only about 0.4sec from the fastest time of the regulars. A little tweaking and a newer motor and ESC and a approximately 6 year old car would be keeping up with current Xray's and the like. 

The LCG has always fascinated me as a car - it suits my driving style almost perfectly and it rarely needs more than a few small tweaks to be near or matching the pace of tracks I have visited while traveling. 

Tigermoth LCG - this chassis doesn't have the front and rear diff braces
 
While on paper it appears simple and well set out, the suspension is frustratingly unreliable and difficult to set to exact camber and castor settings. The single deck and center shaft design makes the car prone to destroying belts and pulleys, especially when running mod motors. It also is very "old school" as far as pulley sizes and diff ratios and there is nothing like a gear diff available. It does have a very good spool idea, which I've recently noticed Tamiya also doing, replacing the diff balls with some sort of friction material. This allows a spool action, but in hard impacts etc the diff can slip which helps prevent breakages.

Despite all its quirks I have persevered with it the longest of any chassis I've ever owned. It has been extensively modified to try and overcome the problems I've encountered - shorter rear belt, various braces to control chassis flex, converting the diff to a Tamiya TA04 diff pulley (allows me to use better diff balls) and modifications to rear uprights to change the arm angle and roll center. I am considering getting a full carbon fiber chassis plate made rather than the CF/Polystyrene original chassis plate. I do have to wonder how practical it is to persevere, but with the current market flooded with almost identical chassis designs, with little to truly differentiate between them, its almost "better the devil you know" then having to start from scratch with a whole new car.

Maybe I should just build my own car...